AIM Diffuse white matter injury is not well detected by cranial ultrasonography (CUS). The aim of this study was twofold: (1) to assess in very preterm neonates the predictive values of individual... Show moreAIM Diffuse white matter injury is not well detected by cranial ultrasonography (CUS). The aim of this study was twofold: (1) to assess in very preterm neonates the predictive values of individual CUS abnormalities for white matter injury on MRI and neurological outcome; (2) to develop a strategy optimizing CUS detection of white matter injury. METHOD Very preterm neonates (n=67; 44 males, 23 females) underwent serial CUS and single MRI. Predictive values of CUS findings for a white matter classification on MRI, individual MRI findings, and neurological outcome at 2 years corrected age were calculated. The effects of timing and frequency of CUS were evaluated. RESULTS Periventricular echodensities (PVEs) predicted abnormal white matter on MRI, but absence of PVEs did not predict absence of white matter changes. Peri-and intraventricular haemorrhage (P/IVH) was highly predictive of abnormal white matter on MRI. Frequency and timing of CUS did not influence predictive values. P/IVH and abnormal ventricular size/shape were reasonably predictive of unfavourable outcome, whereas absence of CUS abnormalities predicted a favorable outcome. INTERPRETATION (1) If PVEs are present, there is a significant chance of abnormal white matter on MRI. (2) Increasing frequency of CUS does not increase its diagnostic performance for white matter injury. (3) P/IVH is highly predictive of abnormal white matter on MRI and reasonably predictive of unfavourable outcome. (4) Absence of PVEs and P/IVH on CUS does not guarantee normal white matter, but predicts a favourable outcome. Show less
Bruine, F.T. de; Wezel-Meijler, G. van; Leijser, L.M.; Berg-Huysmans, A.A. van den; Steenis, A. van; Buchem, M.A. van; Grond, J. van der 2011
To investigate in preterm infants associations between Diffusion Tensor Imaging (DTI) parameters of the posterior limb of the internal capsule (PLIC) and corpus callosum (CC) and age, white matter ... Show moreTo investigate in preterm infants associations between Diffusion Tensor Imaging (DTI) parameters of the posterior limb of the internal capsule (PLIC) and corpus callosum (CC) and age, white matter (WM) injury and clinical factors. In 84 preterm infants DTI was performed between 40-62 weeks postmenstrual age on 3 T MR. Fractional anisotropy (FA), apparent diffusion coefficient (ADC) values and fibre lengths through the PLIC and the genu and splenium were determined. WM injury was categorised as normal/mildly, moderately and severely abnormal. Associations between DTI parameters and age, WM injury and clinical factors were analysed. A positive association existed between FA and age at imaging for fibres through the PLIC (r = 0.48 p < 0.001) and splenium (r = 0.24 p < 0.01). A negative association existed between ADC and age at imaging for fibres through the PLIC (r = -0.65 p < 0.001), splenium (r = -0.35 p < 0.001) and genu (r = -0.53 p < 0.001). No association was found between DTI parameters and gestational age, degree of WM injury or categorical clinical factors. These results indicate that in our cohort of very preterm infants, at this young age, the development of the PLIC and CC is ongoing and independent of the degree of prematurity or WM injury. Show less
Wezel-Meijler, G. van; Leijser, L.M.; Wiggers-de Bruine, F.T.; Steggerda, S.J.; Grond, J. van der; Walther, F.J. 2011
Purpose: To elucidate whether echogenicity (EG) of the basal ganglia and thalami (BGT) represents a physiologic phenomenon in preterm neonates (<32 weeks gestation). Materials and Methods: The... Show morePurpose: To elucidate whether echogenicity (EG) of the basal ganglia and thalami (BGT) represents a physiologic phenomenon in preterm neonates (<32 weeks gestation). Materials and Methods: The study was approved by the medical ethics committee, and informed consent was obtained from the parents. Sequential neonatal cranial ultrasonographic (US) images obtained in 130 preterm neonates were evaluated for EG of the BGT. In 110 of the 130 neonates, MR imaging was performed around or within the first months after term-equivalent age to assess myelination and changes in BGT signal. Cranial US studies obtained in 83 low-risk near-term neonates were used for comparison. Results: Diffuse homogeneous bilateral EG of the BGT was seen in 120 (92%) of 130 preterm neonates and in seven (8%) of 83 low-risk neonates (P < .001). In preterm neonates, EG of the BGT faded with age and was no longer seen 1 month after delivery. This finding was associated with frontal echodensity, which is a normal prematurity-related cranial US phenomenon that occurs in the white matter (P < .001). No association with changes on MR images was found. Conclusion: In preterm neonates, diffuse homogeneous EG of the BGT is a frequent and normal prematurity-related finding. Show less
Wezel-Meijler, G. van; Leijser, L.M.; Wiggers-de Bruine, F.T.; Steggerda, S.J.; Grond, J. van der; Walther, F.J. 2011
OBJECTIVES: To investigate in preterm infants associations between Diffusion Tensor Imaging (DTI) parameters of the posterior limb of the internal capsule (PLIC) and corpus callosum (CC) and age,... Show moreOBJECTIVES: To investigate in preterm infants associations between Diffusion Tensor Imaging (DTI) parameters of the posterior limb of the internal capsule (PLIC) and corpus callosum (CC) and age, white matter (WM) injury and clinical factors. METHODS: In 84 preterm infants DTI was performed between 40-62 weeks postmenstrual age on 3 T MR. Fractional anisotropy (FA), apparent diffusion coefficient (ADC) values and fibre lengths through the PLIC and the genu and splenium were determined. WM injury was categorised as normal/mildly, moderately and severely abnormal. Associations between DTI parameters and age, WM injury and clinical factors were analysed. RESULTS: A positive association existed between FA and age at imaging for fibres through the PLIC (r = 0.48 p < 0.001) and splenium (r = 0.24 p < 0.01). A negative association existed between ADC and age at imaging for fibres through the PLIC (r = -0.65 p < 0.001), splenium (r = -0.35 p < 0.001) and genu (r = -0.53 p < 0.001). No association was found between DTI parameters and gestational age, degree of WM injury or categorical clinical factors. CONCLUSIONS: These results indicate that in our cohort of very preterm infants, at this young age, the development of the PLIC and CC is ongoing and independent of the degree of prematurity or WM injury. Show less
Leijser, L.M.; Bruine, F.T. de; Grond, J. van der; Steggerda, S.J.; Walther, F.J.; Wezel-Meijler, G. van 2010
Cranial ultrasound (cUS) may not be reliable for detection of diffuse white matter (WM) injury. Our aim was to assess in very preterm infants the reliability of a classification system for WM... Show moreCranial ultrasound (cUS) may not be reliable for detection of diffuse white matter (WM) injury. Our aim was to assess in very preterm infants the reliability of a classification system for WM injury on sequential cUS throughout the neonatal period, using magnetic resonance imaging (MRI) as reference standard. In 110 very preterm infants (gestational age < 32 weeks), serial cUS during admission (median 8, range 4-22) and again around term equivalent age (TEA) and a single MRI around TEA were performed. cUS during admission were assessed for presence of WM changes, and contemporaneous cUS and MRI around TEA additionally for abnormality of lateral ventricles. Sequential cUS (from birth up to TEA) and MRI were classified as normal/mildly abnormal, moderately abnormal, or severely abnormal, based on a combination of findings of the WM and lateral ventricles. Predictive values of the cUS classification were calculated. Sequential cUS were classified as normal/mildly abnormal, moderately abnormal, and severely abnormal in, respectively, 22%, 65%, and 13% of infants and MRI in, respectively, 30%, 52%, and 18%. The positive predictive value of the cUS classification for the MRI classification was high for severely abnormal WM (0.79) but lower for normal/mildly abnormal (0.67) and moderately abnormal (0.64) WM. Sequential cUS during the neonatal period detects severely abnormal WM in very preterm infants but is less reliable for mildly and moderately abnormal WM. MRI around TEA seems needed to reliably detect WM injury in very preterm infants. Show less
Wezel-Meijler, G. van; Steggerda, S.J.; Leijser, L.M. 2010
OBJECTIVE: To assess for lenticulostriate vasculopathy (LSV) on cranial ultrasound (cUS) scans of very preterm infants: incidence and aetiology, evolution during neonatal period, association with... Show moreOBJECTIVE: To assess for lenticulostriate vasculopathy (LSV) on cranial ultrasound (cUS) scans of very preterm infants: incidence and aetiology, evolution during neonatal period, association with clinical parameters, and MRI equivalent. DESIGN: Prospective study. SETTING: Tertiary neonatal referral centre. PATIENTS: Very preterm infants (<32 weeks) underwent sequential cUS throughout the neonatal period and MRI around term age. cUS were evaluated for LSV and other changes, and MRI for changes in signal and myelination in deep grey matter. LSV was divided into early-onset (7 postnatal days). Perinatal clinical parameters were collected for all infants and compared between groups. RESULTS: In 22/111 (20%) infants LSV was detected: early-onset in 5 and late-onset in 17. LSV mostly presented some weeks after birth and persisted for several months. There were no associations between LSV and other changes on cUS or deep grey matter changes on MRI. Infants with late-onset LSV were younger and smaller at birth than infants with early-onset LSV. Postmenstrual age at first detection was comparable for both LSV groups. There were no associations between LSV and perinatal clinical parameters, but infants with LSV had less episodes of hypotension than infants without LSV. CONCLUSIONS: LSV is a frequent finding on cUS in very preterm infants, but does not show on MRI. The postmenstrual age, rather than gestational and postnatal age, seems important in LSV development. LSV is not associated with clinical parameters. When encountered in otherwise healthy preterm infants, LSV is probably a benign temporary phenomenon. Show less
Leijser, L.M.; Steggerda, S.J.; Bruine, F.T. de; Zuijlen, A. van; Steenis, A. van; Walther, F.J.; Wezel-Meijler, G. van 2010
Objective: To assess for lenticulostriate vasculopathy (LSV) on cranial ultrasound (cUS) scans of very preterm infants: incidence and aetiology, evolution during neonatal period, association with... Show moreObjective: To assess for lenticulostriate vasculopathy (LSV) on cranial ultrasound (cUS) scans of very preterm infants: incidence and aetiology, evolution during neonatal period, association with clinical parameters, and MRI equivalent. Design: Prospective study. Setting: Tertiary neonatal referral centre. Patients: Very preterm infants (<32 weeks) underwent sequential cUS throughout the neonatal period and MRI around term age. cUS were evaluated for LSV and other changes, and MRI for changes in signal and myelination in deep grey matter. LSV was divided into early-onset (<= 7 postnatal days and late-onset (>7 postnatal days). Perinatal clinical parameters were collected for all infants and compared between groups. Results: In 22/111 (20%) infants LSV was detected: early-onset in 5 and late-onset in 17. LSV mostly presented some weeks after birth and persisted for several months. There were no associations between LSV and other changes on cUS or deer) grey matter changes on MRI, Infants with late-onset LSV were younger and smaller at birth than infants with early-onset LSV. Postmenstrual age at first detection was comparable for both LSV groups. There were no associations between LSV and perinatal clinical parameters, but infants with LSV had less episodes of hypotension than infants without LSV. Conclusions: LSV is a frequent finding on cUS in very preterm infants, but does not show on MRI. The postmenstrual age, rather than gestational and postnatal age, seems important in LSV development. LSV is not associated with clinical parameters, When encountered in otherwise healthy preterm infants, LSV is probably a benign temporary phenomenon. Show less
Infants born very prematurely (gestational age <32 weeks) are at risk of brain injury and neurodevelopmental problems. Imaging the preterm infant__s brain during the neonatal period, using... Show moreInfants born very prematurely (gestational age <32 weeks) are at risk of brain injury and neurodevelopmental problems. Imaging the preterm infant__s brain during the neonatal period, using cranial ultrasonography (cUS) and magnetic resonance imaging (MRI), is important. Our aim was to study and describe brain findings in very preterm infants using modern, high-quality imaging techniques. Part I reviews brain maturation and injury, and imaging thereof, in very preterm infants. Part II discusses our experience on neonatal cUS (Chapters 2-3) and MRI (Chapter 4), and addresses indications, technical aspects, protocols and safety. Part III gives an overview of findings (incidence and evolution) on frequent, sequential neonatal cUS and term-equivalent MRI (Chapter 5), and their relation with perinatal factors (Chapter 6). Part IV focuses on imaging of white matter (Chapters 7-9), describing both normal maturational phenomena and pathological changes and assessing the accuracy of cUS and MRI for these changes. Part V focuses on imaging of deep grey matter (Chapters 10-12), describing both normal maturational phenomena and pathological changes on cUS and assessing their relation with clinical and MRI findings. Part VI reviews the main findings and conclusions of this thesis, and discusses future perspectives and proposals for further research (Chapter 13). Show less
